Modern information networks, such as the Internet and, in particular, the World Wide Web, are data networks using servers to store documents. The servers are interconnected by high-speed data connections. In the WWW, documents are addressed by Uniform Resource Locators (“URL's”). A URL specifies the network support protocol by a prefix in the URL, such as “HTTP” for Hyper Text Transfer Protocol, followed by the host in the data network where the document is stored and the address of the document within that host.
In HTTP data is transmitted to users in a format known as a “page”. Under the HTTP the user interface software, known as the “browser”, cannot start to display a page until a significant portion of the page has been received. It will be appreciated that the page cannot be fully displayed until the entire page has been received. The delay in displaying a page is referred to as “latency”.
Many users of the Internet are connected thereto by relatively slow telecommunication links using a modem and a standard telephone line, for example. The speed with which information is transmitted by commercially available telephone modems is limited to a number of kilobits per second (“kbps”) such as 28.8 kbps or 33.6 kbps. This obviously limits the speed with which pages can be transmitted to a user of the WWW.
The tremendous continuing popularity of the WWW has resulted in a steady growth of the number of users. However, access of large numbers of users to a particular server will slow down the speed with which requests for information are processed.
Further, at present, pages of the Internet can be complex and may take up a relatively huge amount of data. Accordingly, the time for retrieving a complete page using a relatively slow data link can be fairly high.
As a result, today many users complain about the slow speed of the WWW. For the greater part, the latency perceived by users is a result of their relatively slow connection to the Internet and the heavy traffic encountered by a server.
An attempt to eliminate delays in receiving pages from the WWW is to make use of caching techniques. That is, currently available browsers for retrieving data pages are arranged to store received pages in a cache memory. That is, if a user asks for a page which has been asked for previously, the browser will retrieve the particular page from the cache memory.
Caching techniques of this type are, however, only useful if the user retrieves a particular page within a short time after having previously retrieved the same. Otherwise, the browser will not retrieve the page from its cache memory but from the WWW, such that the user again will experience the latency problem.
Further, pages on the WWW will be updated on a regular basis, such that a page which will be stored in a cache memory for a longer time age. By retrieving such a page from the cache memory, the user obviously does not receive the latest information of a particular page or page level.
Navigating the WWW is a complicated task for a number of users, despite the plurality of search tools nowadays available. Further, users who are interested in a particular piece of information on a data page or a data page level, in most cases, are less interested in the graphics and other design features of that data page.
It would be desirable to provide a solution to the main top three frustrations of a user when using the Internet, that is the delay or slowness in fetching pages, the difficulty of navigating the data network, and the sometimes redundant complex and cluttered pages.
In an article by T. S. Loon et al. “Alleviating the Latency and Bandwidth Problems in WWW Browsing”, Proceedings of the USENIX (the Advanced Computing Systems Association) Symposium on Internet Technologies and Systems, December 8-11, 1997 pages 219-230, among others, filtering of HTTP requests and responses is disclosed, adaptively to varying Quality of Service (QoS), in order to reduce data transmission over bottleneck transmission links.
Invocation of an appropriate filter is accomplished by means of a rules database. The goal of the rules database is to allow adaptive filtering based on dynamic network conditions and data types. Every user has his/her own HTTP request filter and HTTP response filter.
Although this filtering technique may provide a solution to the latency problem experienced by a user in case the data are received via a bottleneck transmission link, the user will still be confronted with the sometimes-redundant complex and cluttered data pages if the transmission link to the www provides a sufficient QoS.